JP6426073B2 - Composite fiber and method of manufacturing fabric using the same - Google Patents

Description

  The present invention relates to composite fibers suitable for use in fabrics. More particularly, the present invention relates to a composite fiber suitable for clothing, sleeping equipment and interiors.

BACKGROUND ART In recent years, in the field of clothing such as swimwear and inners, and nightwear and interior goods such as light-shielding curtains and futons, a fabric excellent in heat storage properties and excellent in anti-shedding and light-through prevention properties is required.
A large number of fabrics having heat storage properties and seepage prevention properties have conventionally been proposed. For example, heat is stored in the fabric by kneading specific additives into the fiber, devising the cross-sectional shape of the fiber, devising the fineness of the fiber, devising the processing method of the fiber, devising the structure and processing of the woven or knitted fabric, etc. There are methods such as obtaining a fabric excellent in heat retention effect by giving the property, and obtaining a fabric excellent in anti-susceptibility.

  Specifically, in Patent Document 1, a metal oxide type fine particle infrared absorber having an average particle diameter of 0.5 μm or less is kneaded into polyester fiber at 0.1 to 2.0% by weight based on the fiber weight. It is described that a heat-retaining polyester having excellent sharpness can be obtained by using a heat-retaining polyester fiber characterized by being rare.

  Further, in Patent Document 2, the synthetic polymer forming the core component contains 1.0 to 5.0% by weight of a matting agent, and the synthetic polymer forming the sheath component has a fluorescent brightening agent 0.01. It is described that by using a core-sheath composite yarn which contains .about.1.0% by weight and the cross-section of the core component part is rotationally symmetric, a white fabric excellent in anti-shedding properties is obtained.

Moreover, in recent years, with the improvement of the performance of a camera, one having a through image preventing function is required.
Patent Document 3 proposes a fiber material for skin contact that prevents fluoroscopy by infrared rays formed by unevenly distributing a portion having infrared absorptivity or infrared reflectivity as the light transmission preventing cloth by 40 to 80% of the surface area. ing.
Further, in Patent Document 4, white-based fine particles composed of stannic oxide doped with antimony oxide, or white-based fine particles composed of one obtained by coating stannic oxide doped with antimony oxide on another inorganic fine particle A fabric using 70% by mass or more of synthetic fibers containing 0 to 12.0% by mass, and the infrared ray transmissivity at 1000 nm of the fabric being 40% or less It is done.

JP, 2006-307383, A JP-A-8-60485 Patent No. 4080106 JP, 2010-77575, A

However, the heat-retaining polyester fiber described in Patent Document 1 does not have a sufficient heat storage property, and no description is made on the transmission preventing property.
And the core-sheath composite yarn described in Patent Document 2 is not sufficient in the ability to prevent see-through.
Moreover, although the fiber material of patent document 3 describes that an infrared rays absorbent or an infrared rays reflecting agent is obtained by fixing by post-processing, in the fixing by post-processing, it may separate at the time of use. Although the ability to prevent through-exposure is excellent, there is a problem with its durability.
And although the fabric of patent document 4 is excellent in the transparent image prevention property , it does not become a thing with sufficient see- through prevention property and thermal storage property.
Therefore, an object of the present invention is to solve the above-mentioned problems and to obtain a synthetic fiber suitable for obtaining a fabric which is excellent in both heat storage ability, anti-shearing ability and anti-shearing ability.

In order to achieve the above-mentioned object, the present invention is a post-process by setting it as a composite fiber of the fiber cross-sectional shape which consists of a resin layer which has specific diameter and has a specific diameter, and a resin layer of easy dissolving resin. By melt | dissolving, it discovered that a fiber structure favorable in heat-retaining property, the see- through prevention property , and the through-image preventing property could be obtained.
That is, in order to achieve the above object, the present invention is a composite fiber having a plurality of layers A made of resin A and a layer B made of resin B in the cross section of the fiber, wherein resin A is A fiber-forming polymer containing 2% by mass or more and 15% by mass or less of white conductive particles, and the resin B is a fiber-forming polymer having a higher dissolution rate than the resin A, and an area per layer of A layer Is 0.8 to 60 μm ² , and the composite fiber having an area ratio of A layer to B layer of 35:65 to 85:15 is summarized.
In the composite fiber, the white conductive particles are preferably inorganic particles coated with any one or more of antimony-doped tin or antimony-doped indium, and in particular, the white conductive particles are doped with antimony Preferred is titanium oxide coated with tin.
It is preferable that the said composite fiber is 1.5 micrometers or less in average particle diameter of white electroconductive particle.
The present invention is also a method of producing a fabric comprising microfibers having a single yarn cross-sectional area of 0.8 to 60 μm ² by dissolving and removing the layer B after knitting and weaving the composite fiber. .

  According to the composite fiber of the present invention, it is possible to obtain a fabric which is excellent in both the heat storage property, the see-through prevention property and the through image pickup prevention property.

FIG. 1 is a view showing an example of the cross-sectional shape of the composite fiber of the present invention. FIG. 2 is a view for explaining the flatness of the layer A of the composite fiber of the present invention.

  Hereinafter, the present invention will be described in detail.

First, the present invention is a composite fiber composed of an A layer made of a resin A and a B layer made of a resin B having a higher dissolution rate than the resin A in the fiber cross section.
As the fiber-forming polymer forming the layer A, for example, a fiber-forming thermoplastic resin such as polyester, polyamide, polyurethane or polyolefin can be selected. Examples of the polyester include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), aromatic polyester mainly composed of polyalkylene terephthalate, and aliphatic polyester polylactic acid such as polylactic acid. Examples of the polyamide include polyamide 6, polyamide 11, polyamide 12, polyamide 66, polyamide 610, polyamide 612, polyamide 6T, polyamide 6I, polyamide 9T, polymetaxylene adipamide and the like.

The composite fiber of the present invention is an additive, a lubricant, a matting agent, an antioxidant, a fluorescent whitening agent, an antistatic agent, a light resistant agent, etc. which are generally used as long as the effects of the present invention are not impaired. It may be included.

In the present invention, the resin A contains white conductive particles. As the white conductive particles, for example, tin oxide doped with antimony (hereinafter sometimes referred to as ATO), indium oxide doped with tin (hereinafter sometimes referred to as ITO), etc., titanium oxide or zinc oxide Preferred examples include infrared absorbing particles coated on inorganic particles. These particles may be used alone or in combination.
When used for clothing, bedding, interior goods, etc., titanium oxide coated with tin oxide doped with antimony oxide, which is a type of ATO, is particularly preferably used, from the viewpoint of excellent dyeability and whiteness. .

0.5 micrometer or more is preferable and, as for the average particle diameter of the said white conductive particle, 1.5 micrometer or less is preferable. More preferably, it is 1 μm or less.

  Generally, in synthetic fibers, inorganic particles such as titanium oxide used as a matting agent usually have an average particle diameter of about 0.3 μm. However, white conductive particles such as titanium oxide coated with ATO or ITO in the present invention have an average particle diameter of 0.5 or more and 1.5 μm or less, which is a specific range larger than the average particle diameter. The above range is preferable because infrared rays are converted into heat energy and accumulated as heat to easily exhibit a heat storage effect.

  In the present invention, the content of the white conductive particles relative to the resin A is 2% by mass or more and 15% by mass or less. Preferably, it is 4% by mass or more. Within this range, the heat retaining property, the see-through preventing property and the see-through preventing property are all good, and the spinning operability and the fiber quality are also sufficient.

  The white conductive particles in the present invention preferably have a primary particle diameter of 1.5 μm or less.

  In the present invention, the resin B is a fiber-forming polymer having a higher dissolution rate than the resin A. That is, when the resin B is immersed in the same specific solvent as the resin A, the dissolution rate is higher than that of the resin A. In general, the dissolution rate of the resin B is preferably 10 times or more, more preferably 20 times or more, still more preferably 30 times or more that of the resin A.

For example, when the resin A is a homo polyester, as the resin B, a modified polyester is preferably used. Examples of modified polyesters include phthalic acid having a metal salt of sulfonic acid, modified polyester obtained by copolymerizing adipic acid and polyethylene glycol, and the like. These polyester modified products can be suitably used because the dissolution rate of the resin B is 10 times or more of the dissolution rate of the resin A when the solvent is an aqueous alkali solution or the like.
Since the combination of the homo polyester and the above-described modified polyester does not significantly change the properties of the polymer physical properties, the spinning conditions, the stretching conditions, the false twisting conditions, and the conditions that the post-processing such as weaving or dyeing is also stable It is easy and desirable.

  In addition, among polymers having greatly different properties, as a combination of preferable resin A and resin B, when resin A is polyester, resin B is from the group of polystyrene, polycarbonate, polyamide, polyurethane, polyacrylonitrile, polyethylene, polypropylene The polymer selected is mentioned. If it is a combination of these, the dissolution rates of the resin A and the resin B are largely different, which is preferable.

  Moreover, when resin A is a polyamide, polyester, a polystyrene, a polycarbonate, a polypropylene, polyethylene, polyethylene tetraethylene, a polyacrylonitrile etc. are mentioned as resin B of a suitable combination.

  In addition, as a solvent in case resin B is polyester, 1 to 5 mass% NaOH aqueous solution is mentioned suitably.

  Further, when the properties of the resin A and the resin B are largely different, it is preferable to select a solvent in which one resin dissolves appropriately. For example, when the resin A is a polyester and the resin B is a polyamide, formic acid which dissolves the polyamide is preferably mentioned.

The composite fiber of the present invention is a composite fiber in which a plurality of layers A made of resin A and a layer B made of resin B having a higher dissolution rate than resin A are combined in the fiber cross section (surface perpendicular to the fiber long axis direction). It is.
As a method of obtaining composite fiber by combining layer A and layer B, for example, there is a method of extruding resin A and resin B from separate bases and performing composite spinning to obtain composite fiber.
In the composite fiber of the present invention, by dissolving the layer B, it is possible to appropriately obtain a microfiber consisting of the layer A having a specific diameter. The resulting fabric made of microfibers is excellent in heat storage ability, anti-shearing ability and anti-shooting ability.

As a form which combines A layer and B layer, the sea-island structure which made A layer the sea part and made B layer the island part can be mentioned suitably.
When white conductive particles having a large particle diameter are contained in the resin A, the exposure ratio of the fiber surface of the A layer is preferably 20% or less, and particularly preferably the A layer is not exposed to the fiber surface. Is preferred. As the sea-island type composite fiber of A layer is an island part and B layer is a sea part, the particle diameter of resin A is reduced by reducing the exposure of A layer to the fiber surface or preventing A layer from being exposed to the fiber surface. Even when large white conductive particles are contained, the spinning operability and processability of the composite fiber become good.

Hereinafter, preferred fiber cross-sectional shapes of the composite fiber of the present invention will be illustrated in detail with reference to FIG. In FIG. 1, the hatched portion is an A layer made of resin A, and the white portion is a B layer made of resin B.
For example, the fiber cross section in FIG. 1 (a) is a sea-island structure comprising seven A layers and one B layer, where the A layer is an island portion with a round cross section and the B layer is a sea portion surrounding the A layer. . The island portion in FIG. 1A has a round cross section, but may have a different shape such as a triangle or a polygon such as a square. The number of layer A (the number of island portions) is preferably 2 or more, more preferably 4 or more, and still more preferably 8 or more. The upper limit is preferably about 100 in terms of easy incorporation of white conductive particles and the like in a high concentration and retention of fiber physical properties.
The fiber cross sections in Fig. 1 (b) and (d) consist of eight A layers and one B layer, and the A layer is an island portion with triangular cross section, and the B layer is a radial sea portion that complements the A layer. It is a sea-island structure. In this figure, the cross-sectional shape of the island portion is a triangle, but it may be a polygon such as a quadrangle, or another irregular cross-section. The layer B in FIG. 1 (b) has a shape extending radially from the center of the fiber and is exposed on the surface of the fiber. The layer B in FIG. 1 (d) has a shape extending radially from the center of the fiber, the layer B covers the layer A, and the layer A is not exposed to the fiber surface. When the layer A is exposed to the fiber surface, the exposure ratio of the layer A to the fiber surface is preferably 80% or less from the viewpoint of preventing wear of metals such as goded rolls. In the case of this shape, the number of A layers (the number of island portions) is preferably 3 or more, and the upper limit thereof is preferably about 30.
The fiber cross sections in FIGS. 1 (c) and 1 (e) consist of nine A layers and one B layer, and the A layer is an island with a round cross section at the center of the fiber and a square cross section near the outer circumference. It is an island part, B layer is a sea part of the shape which complements A layer, B layer is a sea-island structure of a hollow shape and the shape extended radially. Although the shape of the layer A is a circle or a square, it may be a polygon such as a triangle or a pentagon, or any other different cross section.
In FIG. 1 (c), the layer A is exposed on the fiber surface, and in the case of FIG. 1 ( e ), the layer A is not exposed. When the layer A is exposed to the fiber surface, the exposure ratio of the layer A to the fiber surface is preferably 80% or less from the viewpoint of preventing wear of metals such as goded rolls. In the case of this shape, the number of A layers (the number of island portions) is preferably 3 or more, and the upper limit thereof is preferably about 30.
Among these, FIG. 1 (b, c, d, e) is preferable from the viewpoint of the heat storage property, the light transmission preventing property, and the light transmission preventing property. In particular, it is preferable that the number of A layers in FIG. 1 (b, c, d, e) is 8 or more and the flatness of the A layers is high.

The aspect ratio of the layer A in the conjugate fiber of the present invention is preferably 0 to 90% from the viewpoint of improving the yarn quality. Moreover, it is preferable that it is 20 to 80% from the point of heat storage property, the ability to prevent see-through, and the ability to prevent light transmission.
With reference to the description of FIG. 2, assuming that the length of the long side of layer A is a and the length of the short side of layer A is b, the aspect ratio of layer A is the aspect ratio (%) = [(a It is a value calculated as −b) × 100 / a].

  The fiber surface exposure of the layer A in the conjugate fiber of the present invention is preferably 80% or less, more preferably 50% or less, and still more preferably not exposed. When the exposure of the layer A to the fiber surface is very large, the balance between the heat storage property, the see-through prevention property, the anti-shooting property, the spinning operability, and the post processability tends to be impaired.

  The ratio (area ratio) of each of the composite fiber of the present invention in the layer A and the layer B is preferably 35:65 to 85:15, and more preferably 60:40 to 80:20. When the A layer is less than 35%, the resin B component to be dissolved in forming the microfibers is large, which increases the cost, and when the A layer exceeds 85%, it is difficult to penetrate inside the fiber, and dissolution spots It does not break up cleanly and there is a tendency that microfiber can not be obtained stably.

The area per layer of the layer A in the composite fiber of the present invention is 0.8 to 60 μm ² from the viewpoint of heat storage property, anti-smearing property and anti-shearing property. Preferably a 5 to 30 [mu] m ^2, more preferably 8~25μm ^2. When the area of one A layer is less than 0.8 μm ² , when the particle diameter of the white conductive particles is large, a normal fiber cross section is not formed. Within the above range, after dissolving the layer B, the heat storage property, the anti-shearing property and the anti-shearing property are excellent while maintaining the quality of the yarn. In the present invention, the area per layer of the layer A in the composite fiber is the average area of the layers of the layer A. Further, the area of each A layer is preferably within ± 25% of the average area per A layer.

  The strength of the composite fiber of the present invention is preferably 2.8 cN / dtex or more, more preferably 3 cN / dtex or more. When it is less than 2.8 cN / dtex, the strength of the microfiber obtained by the alkali reduction is also lowered, and there is a tendency that fuzz and release of fine particles are likely to occur.

The elongation of the composite fiber of the present invention is preferably 18 to 150%, more preferably 20 to 120%. When the elongation is less than 18%, the elongation of the microfiber obtained by reducing the amount of alkali decreases, and the fluff and the release of fine particles tend to be easily generated. If the elongation exceeds 150%, the strength after alkali loss tends to be poor.

The composite fiber of the present invention preferably has a heat storage property shown below of at least 1.5 ° C. in comparison with a reference fabric.
The heat storage property is determined by irradiation with a reflex lamp using a fabric (reference sample) having a basis weight of 50 g / m ² consisting of fibers not containing white conductive particles and a fabric (comparative sample) consisting of fibers to be measured. The degree to which the temperature of the reference sample rises relative to the sample is measured as described later, and the value of "comparative sample-reference sample" is taken as the value of the heat storage capacity (° C).
The heat storage property (temperature rise from the reference sample) of the composite fiber of the present invention is preferably 1.5 ° C. or more, more preferably 3 ° C. or more, and the higher the value of the heat storage property, the better the heat storage effect. .

  The composite fiber of the present invention preferably has a transmittance of 20% or less in the wavelength range of 400 to 600 nm, 20% or less in the wavelength range of 600 to 800 nm, and 20% or less in the wavelength range of 800 to 1200 nm. In the visible light region in the wavelength region of 400 to 800 nm, visible light tends to easily pass through when the clothes are worn under conditions where the transmittance exceeds 20%, and the fabric tends to be transparent. In addition, even when it gets wet, it can be easily seen through. If the transmittance is 20% or less, it is difficult for the naked eye to determine the transparency, and there is a tendency to be able to protect privacy. Furthermore, in the near infrared region of 800 to 1200 nm, under conditions where the transmittance exceeds 20%, it is easily taken through by the infrared camera and there is a tendency that privacy can not be protected, and the transmittance is 20% or less By doing this, you can easily prevent it.

The composite fiber of the present invention can be made into a cloth made of microfibers by dissolving the layer B and removing a part or all of the layer after knitting and weaving.
The single fiber cross-sectional area of the microfiber after dissolution is preferably 0.8 to 60 μm ² . When the single yarn cross-sectional area is less than 0.8 μm ² , when white conductive particles with good heat storage capacity are used, after dissolution, generation of fiber fluffing, thread breakage, release of fine particles, etc. results in weak yarns, etc. There is a fear. When the single fiber diameter exceeds 60 μm ² , the mesh size of the fabric becomes large, so that a good transmittance can not be obtained, so that it is easy to cause transparency, and good heat storage property, transparency preventing property and transparency There is a tendency that the anti-shooting property can not be obtained. Therefore, the single Itodan area of microfibers after dissolution preferably 0.8～60Myuemu ^2, and more preferably from 5 to 30 [mu] m ^2.

  The strength of the microfiber after dissolving and removing the layer B of the conjugate fiber of the present invention is preferably 2.8 cN / dtex or more, more preferably 3.0 cN / dtex.

  The elongation of the microfiber after dissolving and removing the layer B of the composite fiber of the present invention is preferably 18 to 150%, more preferably 20 to 120%.

Next, a preferred method for producing the composite fiber of the present invention will be described more specifically.
The following is an example of a method for producing a composite fiber using a polyester resin to which white conductive particles are added as the resin A, and a copolymer polyester having a larger dissolution rate than the resin A as the resin B.

First, a polyester resin (resin A) containing 2 to 15% by mass of white conductive particles, and a copolymer polyester (resin B) with high alkali solubility are prepared.
Each of these resins is melted and discharged from a spinneret. Subsequently, the yarn is cooled to give an oil, and then it is drawn between the first goded roll (hereinafter sometimes referred to as GR1) and the second godd roll (hereinafter sometimes referred to as GR2) and heat-treated; It can be peeped to obtain the composite fiber of the present invention.

  As a spinning temperature (temperature discharged from a spinneret), for example, 270 to 295 ° C is preferable, and more preferably 280 to 295 ° C.

  The spinning speed (in the above, the speed at which the undrawn yarn is wound up) is, for example, preferably 800 to 1800 m / min, and more preferably 800 to 1500 m / min.

  The heat treatment temperature in the stretching step is, for example, preferably 100 to 180 ° C., and more preferably 120 to 160 ° C.

  As a picking speed, 3000-4500 m / min is preferable, More preferably, it is 3000-4000 m / min.

The above illustrates the method for producing the synthetic fiber of the present invention by the method (direct drawing method) of drawing, heat treating and then winding the undrawn yarn without taking it up once, but the undrawn yarn is taken up once Then, it may be manufactured using a method of stretching (conventional method).
In this case, the spinning speed is, for example, preferably 800 to 1800 m / min, and more preferably 800 to 1500 m / min.
The heat treatment temperature in the stretching step is, for example, preferably 100 to 180 ° C., more preferably 120 to 160 ° C.
The stretching speed is, for example, preferably 500 to 1200 m / min, and more preferably 600 to 1000 m / min.

  The composite fiber of the present invention may be in any form such as undrawn yarn, semi-drawn yarn (highly oriented undrawn yarn), drawn yarn and the like.

In the manufacturing method described above, the method for obtaining a drawn yarn has been illustrated, but in the case of obtaining a highly oriented undrawn yarn, the resin is melted and discharged as in the conventional method described above, followed by cooling and oiling agent after the application, leading to the first Godeddororu can then be through the second Godeddororu first Godeddororu same speed obtained by winding a semi-drawn yarn as highly oriented in the bobbin. The uniform velocity of each goded roll is preferably about 3000 to 4500 m / min, and more preferably 3000 to 4000 m / min.

The composite fiber of the present invention may be used as a raw yarn as it is when making, knitting, etc., but it may be used after being processed so as to make the fiber bulky, such as false twisting, push processing, knit denit processing . Further, by performing such processing, one having more excellent heat retention, heat storage property, and seepage prevention property can be obtained, and when knitting and knitting can be performed, since the stitches and weaves can be made dense, further, It becomes easy to obtain the heat storage property, the see-through prevention property, and the through-photographing prevention property.

  The present invention will be described in detail by way of examples. The present invention is not limited to the examples described below. In addition, the measuring method in an Example and a comparative example is as follows.

A. Breaking Strength, Breaking Elongation Measured according to JIS-L-1013 using an AGS-1 KNG Autograph Tensile Tester manufactured by Shimadzu Corporation under the conditions of a sample yarn length of 20 cm and a constant tensile speed of 20 cm / min. The value obtained by dividing the maximum value of the load in the load-elongation curve by the fineness is taken as the breaking strength (cN / dtex), and the elongation at that time is taken as the breaking elongation (%).
B. Average particle size Photographed using a transmission electron microscope (transmission electron microscope JEM-1230 manufactured by JEOL Ltd.), and the volume-based horizontal uniform diameter was measured with an automatic image processor (LUZEX AP (manufactured by Nireco)). It measured and calculated specific gravity, and calculated | required the average particle diameter of the weight average.
C. If the processability of the spinning process is good, the product is evaluated as も の.
D. Thermal storage property evaluation The fiber obtained from the Example and the Comparative Example was used as a yarn sample, and a microfiber fabric was produced by Method E described later, and this microfiber fabric was used as a comparison sample. Then, the same sample as the comparative sample was prepared except that the white conductive particles were not contained, and was used as a reference sample. Thereafter, in a room at a temperature of 22 ° C. and a humidity of 60%, a thermometer is placed on the flat surface of foam polystyrene, a reference sample is placed above it, and a reflex lamp is placed 50 cm above the reference sample. The light of 500 W was irradiated from the ref lamp, and the temperature of the reference sample when 10 minutes passed was measured, and it was set as A1. Similarly, the temperature of the comparison sample after irradiation with the reflector lamp for 10 minutes is measured, and is referred to as S1.
The heat storage capacity is calculated by the following equation.
Heat storage property (° C.) = (S1)-(A1)
E. Preparation of microfiber cloth
After preparing a tubular knit fabric by using two yarn samples as double yarns, the number of wales is 30 / 2.54 cm and the number of courses is 60 so that the fabric weight of the fabric obtained by alkali treatment is 50 g / m ^2. Prepare a tubular knit fabric produced with a 2.54 cm tubular knit fabric. Then, 2% by weight aqueous NaOH solution is brought to a temperature of 98 ° C., treated for 15 minutes under a bath ratio of 1:50, alkali reduction is carried out, and resin B is dissolved away, dehydrated and air dried to prepare a microfiber fabric. .
F. Transmittance evaluation The transmittance in the wavelength region of 400 to 1200 nm was measured with a Shimadzu self-recording spectrophotometer (UV-3101 PC / MPC-3100). Average values were calculated for the following three areas.
(1) Wavelength range 400 to 600 nm
(2) Wavelength range of 600 to 800 nm
(3) Wavelength range 800 to 1200 nm
In addition, (1) and (2) are visible light area | regions, and when all were 20% or less, it was judged that shelving prevention property was favorable. (3) is a near infrared region, and when it is 20% or less, it was judged that the transmission preventing property is good.

Example 1
A master batch in which 30 mass% of titanium oxide (ATO coated titanium oxide) coated with polyethylene terephthalate as a white conductive particle and doped with antimony oxide having an average particle diameter of 0.6 μm is contained as resin A The following polyethylene terephthalate (intrinsic viscosity IV: 0.670 dl / g) was prepared, and chip-blended such that ATO-coated titanium oxide had a concentration of 2 % by mass was prepared. Further, as resin B, a polyethylene terephthalate (alkali-soluble PET) was prepared, in which sulfoisophthalic acid and polyethylene glycol were copolymerized so that the dissolution rate in 2% by mass aqueous NaOH solution was 20 times greater than that of resin A. Using these resins, a sea-island type spinneret shown in FIG. 1A having a round discharge hole at a spinning temperature of 295 ° C., resin B in the sea area, resin A in the nine island areas, and resin A : B was discharged so that it might become 75:25 (area ratio). Subsequently, the yarn is cooled, oiled, heat treated at 90 ° C. with GR1 velocity 1000 m / min, heat treated at 135 ° C. with GR2 velocity 3800 m / min, wound as drawn yarn, nine A layers with a denier of 70 dtex / 25 f And a composite fiber (layer diameter of each segment of layer A: 4.8 .mu.m).

Comparative Example 1
Polyethylene terephthalate not containing ATO-coated titanium oxide (intrinsic viscosity IV = 0.670 dl / g) was discharged from a spinneret having a round discharge hole at a spinning temperature of 295 ° C. Subsequently, the yarn is cooled, an oiling agent is applied, heat treatment is performed at a GR1 velocity of 1000 m / min, 90 ° C., GR2 velocity 3800 m / min, heat treatment at 135 ° C., the drawn yarn is wound, and single fibers having a denier of 56 dtex / 24 f are obtained. The

[Examples 2 to 4, Comparative Examples 2 and 3]
A composite fiber was obtained in the same manner as Example 1, except that the content of the ATO-coated titanium oxide particles was changed to 5% by mass, 10% by mass, 15% by mass, 1.5% by mass, and 20% by mass. In Comparative Example 3 in which the resin A contained 20% by mass, no composite fiber was obtained.

[Examples 5, 6]
A composite fiber was obtained in the same manner as in Example 1 except that the white conductive particles were changed from ATO-coated titanium oxide to ITO-coated titanium oxide, and the content was changed as shown in Table 1.

[Examples 7 to 9]
A composite fiber was obtained in the same manner as in Example 2 except that the average particle size of the ATO-coated titanium oxide particles was changed as shown in Table 1.

The microfiber cloth was produced by the method of said E of Examples 1-9.
The raw materials and physical properties of the fibers obtained from Examples 1 to 9 and Comparative Examples 1 and 2 above, the physical properties of the fibers and fabrics after alkali treatment, and the results of heat storage evaluation and transmittance evaluation are shown in Table 1.

A layer is made of PET having an average particle diameter of 0.6 μm and a concentration of 2% by mass or more of conductive white-based particles obtained from Examples 1 to 6, and a layer of alkali-soluble PET of resin B is a layer B. Resin A: Sea-island type composite fiber with resin B = 75: 25 and number of layer A (number of islands) of 9 is good in spinnability, and fiber properties are also good with strength of 3 cN / dtex or more and elongation around 30%. And were suitably applicable to knitting and weaving. Moreover, the value of the heat storage property of the microfiber fabric using the conjugate fiber obtained from Examples 1-6 is 3.8 degreeC or more, and was excellent in heat storage property. In the visible light region (400 to 600 nm and 600 to 800 nm), the transmittance was 20% or less, and the effect of preventing light transmission was obtained. Moreover, the transmittance | permeability of a near-infrared area | region (800-1200 nm) was 20% or less, and was excellent in the transparent image prevention effect.
The synthetic fiber of the polyethylene terephthalate alone obtained from Comparative Example 1 did not have good heat storage properties, transparency prevention properties and transparency prevention properties.
The composite fiber in which the density | concentration of the white electroconductive particle obtained from the comparative example 2 is as low as 1.5 mass% was inferior to heat storage property, the ability to prevent see-through, and the ability to prevent through-photographing compared with the Example goods.
The sea-island type composite fiber having 9 pieces of number (number of islands) of layer A containing 5% by mass of particles smaller than 2 μm of white conductive particles obtained from Examples 7 to 9 has good spinning operability and fiber physical properties. The heat storage property, the see-through prevention property, and the through-shooting prevention property were both excellent.

Comparative Example 4
Masterbatch containing 30% by mass of ATO with an average particle diameter of 0.6 μm in polyethylene terephthalate as resin for the core, and content of white conductive particles of polyethylene terephthalate (intrinsic viscosity IV: 0.670 dl / g) A chip-blended product was prepared such that the weight of the powder was 5% by mass. Further, as the resin of the sheath portion, a polyester containing 0.4% by mass of titanium oxide having an average particle diameter of 0.3 μm was prepared. These resins were discharged from a spinneret having a round discharge hole at a spinning temperature of 295 ° C. such that the core: sheath (resin A: resin B) was 3: 1 (area ratio). Subsequently, the yarn is cooled, oiled, heat treated at 90 ° C. with a GR1 velocity of 1000 m / min, heat treated at 135 ° C. at a GR2 velocity of 3800 m / min, wound with a drawn yarn, core / sheath composite fiber with a denier of 84 dtex / 24 f Obtained.

Comparative Example 5
Core-sheath composite fibers were obtained in the same manner as in Comparative Example 4 except that the fineness and the number of filaments were changed.

[Examples 2 and 10 to 15, Comparative Example 6]
A composite fiber was obtained in the same manner as in Example 2 except that the fiber cross section was changed as described in Table 2.

The raw materials and fiber physical properties of the fibers obtained from Examples 2 and 10 to 15 and Comparative Examples 1 and 4 to 6, the physical properties of the fiber after alkali treatment and the physical properties of the fabric, and the evaluation results are shown in Table 2.

The composite fibers obtained from Examples 2 and 10 to 15 have no problem in spinning operation, and the fiber physical properties are good with strength of 3 cN / dtex or more, elongation around 30.0%, and can be suitably applied to knitting and weaving. It was a thing. Moreover, the microfiber fabric obtained using these fibers had a heat storage property value of 2.4 ° C. or more, and had a good heat storage property, and was excellent in the ability to prevent see-through and the ability to prevent light transmission.
In addition, referring to the transmittances of Examples 2, 11 and 12, the cross section of the layer A (island portion) has a higher cross section than that of the round cross section, and the one with a higher flatness has the ability to prevent penetration. And it was excellent in penetration photography prevention.
In addition, as to the flatness, Example 1 (round cross section): 0% (long side a = short side b = 4.8 μm), Example 11 (triangular cross section): 35% (long side a = 7.4 μm, short) Side = 4.8 μm, Example 12 (square cross section): 20% (long side a = 5 μm, short side = 4 μm). The higher the aspect ratio, the higher the heat storage property, and the lower the transmittance at all the wavelengths of 400 to 1200 nm. As a result, the light transmission preventing property and the light transmission preventing property are improved. This is that by the fact that the aspect ratio is high, light such as sunlight is efficiently absorbed, the heat conversion is performed to increase the heat storage property, and the aspect ratio becomes high, and the contact area with the skin is improved. It can be inferred that the see-through preventing property and the through image preventing property are improved by this.
The composite fibers obtained from Comparative Examples 4 and 5 were inferior in the ability to prevent see-through and the ability to prevent through-photographing as compared with the examples. Since this is not microfiberized, the gap of the fabric is increased, and visible light and light in the near infrared region are more likely to be transmitted, and both the visible light and near infrared transmittances exceed 20%, and it is transparent It is thought that it has become a thing with a small prevention property and a penetration photography prevention property.
The composite fiber obtained from Comparative Example 6 had fluff and broken yarn, and had poor spinnability and inferior heat storage property. In addition, the obtained microfiber fabric was frequently subjected to single thread breakage, fuzz, insufficient strength and the like.

[Examples 16 to 18, Comparative Example 7]
A composite fiber was produced in the same manner as in Example 2 except that the ratio of layer A to layer B was changed.

The raw materials, fiber physical properties, and evaluation results of the fibers obtained from Examples 2 and 16 to 18 and Comparative Examples 1 and 7 are shown in Table 3.

The composite fiber obtained from Examples 2 and 16 to 18 had good fiber physical properties such as strength of 3.4 cN / dtex or more, elongation around 30%, and was suitably applicable to knitting and weaving. The value of the heat storage property is excellent at 4.8 ° C. or more, and in the visible light region (400 to 600 nm and 600 to 800 nm), the transmittance is 20% or less, and the effect of preventing light transmission is obtained. Moreover, in the near infrared region (800 to 1200 nm), the transmittance was 14.5% or less, and an effect could be found for transmission through with an infrared camera. Therefore, the microfiber cloth obtained in the above-mentioned example was excellent in heat storage and shedding prevention.
Comparative Example 7 in which the layer A: layer B was 90: 10 had poor spinning operability and was inferior in the ability to prevent see-through as compared with the product of the example.

  According to the composite fiber of the present invention, by dissolving the layer B in a later step, it is possible to obtain a fabric having a heat storage property, a see-through prevention, and an ability to prevent see-through. In addition to being expected to be used, it also has the effect of shielding light, and it can also be expected to be used for curtain materials such as blind curtains, voice curtains and lace curtains, interior applications for screen doors and bedding applications such as futons and bedding. .

A: Resin A (A layer)
B: Resin B (B layer)

Claims (5)

The fiber is a composite fiber having a plurality of layers A made of resin A and a layer B made of resin B in the fiber cross section, wherein the resin A is a fiber containing 2% by mass or more and 15% by mass or less of white conductive particles It is a forming polymer, and resin B is a fiber forming polymer having a larger dissolution rate than that of resin A, and the area per layer of layer A is 0.8 to 60 μm ² . A composite fiber having an area ratio of 35:65 to 85:15. The composite fiber according to claim 1, wherein the white conductive particles are inorganic particles coated with any one or more of antimony-doped tin or antimony-doped indium. The composite fiber according to claim 1 or 2, wherein the white conductive particles are antimony-doped tin-coated titanium oxide. The composite fiber according to any one of claims 1 to 3, wherein the average particle size of the white conductive particles is 1.5 μm or less. A method for producing a fabric comprising microfibers having a single yarn cross-sectional area of 0.8 to 60 μm ² by preparing a composite fiber according to any one of claims 1 to 4 and then dissolving and removing the layer B.

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